Endocrine late effects in survivors of infantile acute lymphoblastic leukemia.

Infantile acute lymphoblastic leukemia (ALL) is a rare disease. In survivors, endocrine late effects, such as growth disorder and hypothyroidism, have been reported, but gonadal function remains unclear. Infantile ALL frequently requires transplantation and higher doses of alkylating agents, even in the absence of transplantation. Some studies in childhood cancer survivors reported that a cyclophosphamide equivalent dose (CED) of > 20 g/m2 was associated with testosterone deficiency in boys and > 8 g/m2 with ovarian dysfunction in girls. We retrospectively reviewed the treatment and endocrine function of 6 infantile ALL survivors treated at our hospital using their medical records. The patients' age at the time of the study was between 12 and 26 yr. One patient had 0 transplant, four of them had 1 transplant, and one had 2 transplants, with CEDs of 3, 9-11, and 24 g/m2 respectively. Two patients had short stature, and two patients experienced hypothyroidism. All three girls with a CED of 9-11 g/m2 had primary hypogonadism, and the boy with a CED of 24 g/m2 had high LH and FSH levels, suggesting testosterone deficiency and spermatogenesis disorders. In conclusion, gonadal function, growth and thyroid function should be carefully monitored in infantile ALL, and CED may be useful for predicting the development of hypogonadism.

Plasma-derived factors VIIa and X mixtures (Byclot®) significantly improve impairment of coagulant potential ex vivo in plasmas from acquired hemophilia A patients.

A combined product of plasma-derived factor (F)VIIa and FX (pd-FVIIa/FX; Byclot®) is currently available for the hemostatic treatment of hemophilia A and B patients with inhibitors in Japan. Limited information is available, however, on its coagulant effect in acquired hemophilia A (AHA). In the present study, we assessed the coagulant effect of pd-FVIIa/FX on impairment of coagulation potentials in AHA. The bypassing agents, pd-FVIIa/FX, recombinant FVIIa (rFVIIa), and activated prothrombin complex concentrates (aPCC) were spiked with normal plasma preincubated with anti-FVIII monoclonal antibody (AHA-model plasma), and added to plasmas from AHA patients. Clot waveform analysis (CWA) triggered by the mixture of tissue factor and ellagic acid was subsequently performed. In the AHA-model, pd-FVIIa/FX improved all of the CWA parameters in a dose-dependent manner, irrespective of epitope specificity, with significant improvements relative to rFVIIa and aPCC. The coagulant effect of pd-FVIIa/FX at 1.6 µg/mL (corresponding to 120 µg/kg infusion) at the maximum therapeutic dose was outside the normal range. Moreover, the addition of pd-FVIIa/FX led to a greater improvement in the coagulant potentials in AHA plasmas than those of rFVIIa and/or aPCC. These data suggest that pd-FVIIa/FX significantly improves the impaired coagulant potentials in AHA and is potentially therapeutic.

Disordered hemostasis associated with severely depressed fibrinolysis demonstrated using a simultaneous thrombin and plasmin generation assay during L-asparaginase induction therapy in pediatric acute lymphoblastic leukemia.

BACKGROUND: L-asparaginase (L-Asp)-associated thromboembolisms are serious complications in pediatrics patients with acute lymphoblastic leukemia (ALL), especially at ≥10.0 years old, but the pathogenesis remains to be clarified. PROCEDURE: We conducted a multicenter, prospective study of 72 patients with ALL aged 1.0 to 15.2 years treated with either a Berlin-Frankfurt-Münster (BFM) 95-ALL oriented regimen or Japan Association of Childhood Leukemia Study ALL-02 protocol. We divided patients into each treatment protocol and investigated the dynamic changes in coagulation and fibrinolysis using simultaneous thrombin and plasmin generation assay. Patients' plasma samples were collected at the prephase (T0), intermittent phase (T1), and postphase of L-Asp therapy (T2), and postinduction phase (T3). Measurements of endogenous thrombin potential (T-EP) and plasmin peak height (P-Peak) were compared to normal plasma. RESULTS: None of the cases developed thromboembolisms. Median ratios of T-EP and P-Peak for the controls in the JACLS group were 1.06 and 0.87 (T0), 1.04 and 0.71 (T1), 1.02 and 0.69 (T2), and 1.20 and 0.92 (T3), respectively, while those in the BFM group were 1.06 and 1.00 (T0), 1.04 and 0.64 (T1), 1.16 and 0.58 (T2), and 1.16 and 0.85 (T3), respectively. In particular, P-Peak ratios were depressed at T1 and T2 compared to T0 in the BFM group (P < .01). Moreover, P-Peak ratios in patients ≥10.0 years old were lower at T1 in the BFM group (P = .02). CONCLUSIONS: The results demonstrated that hemostatic dynamics appeared to shift to a hypercoagulable state with marked hypofibrinolysis associated with L-Asp therapy, especially in patients ≥10.0 years old following the BFM regimen.

Hemostatic function in hyperfibrinolytic disseminated intravascular coagulation.

BACKGROUND: Global hemostatic mechanism(s) in patients with disseminated intravascular coagulation (DIC) are poorly understood. There are few diagnostic criteria of DIC based on overall or global hemostatic mechanisms. METHODS: We have assessed in detailed the dynamic global hemostatic changes using thrombin and plasmin generation assay (T/P-GA), clot fibrinolytic waveform analysis (CFWA) and not-activated rotational thromboelastometry (NATEM), in a young girl with DIC associated with acute myeloid leukemia (AML). The ratios of endogenous thrombin potential (T-EP) and plasmin lag time (P-LT) relative to normal plasma was sourced from pooled normal plasma from healthy volunteers on T/P-GA. RESULTS: The inverse P-LT ratio prior to tranexamic acid (TXA) treatment was greater than the T-EP ratio (1.1-2.8 and 0.83-1.2, respectively). Significant reduction in inverse P-LT ratio (0.084-1.3) was observed after TXA treatment. The interval from clotting to the initiation of fibrinolysis (fibrinolysis lag time: FLT) in CFWA was significantly shorter than the control at onset (74.2-91.6 s vs 109 s), indicating enhanced fibrinolysis. Data from an adult with acute promyelocytic leukemia-associated DIC also supportively showed a high inverse P-LT ratio (2.1) and shortened FLT (83.7 s). The clotting time in patient whole blood using NATEM-mode during an episode of severe epistaxis markedly shortened beyond control, but returned to normal after the addition of an anti-tissue factor (TF) monoclonal antibody. CONCLUSION: The release of intravascular TF contributed to sustained activation of coagulation and subsequent fibrinolytic activity in this patient with AML-associated DIC, and T/P-GA could provide better quantitative data than conventional assays in these circumstances.

Fibrinolytic abnormality associated with progression of pediatric solid tumor.

BACKGROUND: Thrombosis and hemorrhage are serious complications of pediatric solid tumor, and enhanced fibrinolysis associated with disseminated intravascular coagulation (DIC) is often observed. Fibrinolytic enzymes also play an important role in metastasis. Limited information is available, however, on the assessment of overall hemostatic function in children with malignant solid tumor. METHODS: We have investigated the comprehensive hemostatic potential in these circumstances using simultaneous thrombin/plasmin generation assay (T/P-GA). Endogenous thrombin potential (T-EP) and plasmin peak height (P-Peak) were measured using T/P-GA in six children newly diagnosed with solid tumor at regular intervals during chemotherapy at the present hospital from 2013 to 2016. Four patients with metastasis were defined as the advanced group, and the other patients were defined as the non-advanced group. RESULTS: In the advanced group, the ratio of P-Peak to normal was higher than the slightly increased ratio of T-EP to normal (range, 1.2-2.1 vs 1.1-1.5, respectively). In the non-advanced group, however, the P-Peak ratio was relatively lower than the slightly increased T-EP ratio (range, 1.0-1.5 vs 1.1-1.5, respectively). Fibrin-fibrinogen degradation product was elevated in all patients except in one non-advanced brain tumor patient during this induction therapy (maximum, 11.6-161 µg/mL). CONCLUSIONS: Uncontrolled fibrinolysis together with an imbalance between coagulation and fibrinolytic potential might lead to DIC. Further research is warranted to clarify comprehensive hemostatic function in pediatric patients with solid tumors to establish optimal supportive therapy, and possibly limit tumor progression in these critical disorders.

Potentially life-threatening coagulopathy associated with simultaneous reduction in coagulation and fibrinolytic function in pediatric acute leukemia after hematopoietic stem-cell transplantation.

The pathogenesis of sinusoidal obstruction syndrome (SOS) and thrombotic microangiopathy (TMA) after hematopoietic stem cell transplantation (HSCT) is poorly understood, and limited information is available on global hemostatic function in HSCT. We assessed changes in coagulation and fibrinolysis using a simultaneous thrombin and plasmin generation assay (T/P-GA) during HSCT. Measurements of endogenous thrombin potential (T-EP) and plasmin peak height (P-Peak) using T/P-GA in six pediatric acute leukemia patients treated with HSCT were compared to normal plasma. In the SOS case, the ratios of T-EP and P-Peak to normal were simultaneously decreased at four weeks post-HSCT (Pre; ~1.1/1.1-1.4, Week+4; 0.14/0.0084, respectively). Similarly, in the TMA patient, both ratios were decreased at 3 weeks and recovered after 8 weeks (Pre; 1.2/~0.95, Week+3; 0.59/0.22, Week+8; 1.2/0.64-0.85). In the other patients, when SOS/TMA was not evident, the T/P-GA data remained within normal limits. These findings suggest that the simultaneous reduction of coagulation and fibrinolytic function in patients developing SOS/TMA can lead to a life-threatening coagulopathy. Further research is warranted to clarify global hemostatic function after HSCT to establish optimal supportive therapy for these critical clinical disorders of hemostasis.

Successful non-myeloablative allogenic bone marrow transplantation in a child with severe congenital neutropenia complicated by chronic pulmonary infection.

We herein describe a 2-year-old boy with severe congenital neutropenia (SCN) who was successfully treated with reduced-intensity bone marrow transplantation (HSCT). He had suffered recurrent episodes of bacterial pneumonia from 12 months of age, and was found to have severe neutropenia with white blood cell counts below 100/µl. The patient harbored a heterozygous missense mutation in ELANE exon 4 (p.Gln134Pro, NM_001972.2: c.401A>C). This was a novel mutation. Due to intractable pneumonia and severe persistent neutropenia, reduced-intensity HSCT was performed from an HLA-matched sibling donor. The preparative regimen consisted of melphalan, fludarabine, and 4 Gy of total body irradiation. Hematopoietic engraftment was rapidly obtained, i.e., by day +14, and complete donor chimerism was subsequently achieved. The lung complications observed pre-transplantation markedly improved after neutrophil recovery, i.e., by day +60. We concluded that HSCT is a useful treatment for SCN patients, especially for those at high risk of leukemic transformation. Fludarabine-based reduced-intensity HSCT may represent a safe and effective therapeutic option for patients with SCN who need HSCT even if they have intractable infectious complications.